1986/11/01 by Ingeborg D. Bossert, L. Y. Young · 2 citations
Environmental Science · Chemistry · #Microbial bioremediation and biosurfactants #Radioactive element chemistry and processing #Wastewater Treatment and Nitrogen Removal #Denitrifying bacteria #Electron acceptor #Chemistry #Electron donor #Dehydrogenation #Nitrate #Anoxic waters #Photochemistry #Stoichiometry #Substrate (aquarium) #Inorganic chemistry #Catalysis #Organic chemistry #Denitrification #Environmental chemistry #Biology #Nitrogen
paper · pdf · doi:10.1128/aem.52.5.1117-1122.1986
openalex publication_date 1986/11/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Metabolism of p-cresol (pCr) under nitrate-reducing conditions is mediated by the denitrifying bacterial isolate PC-07. The methyl substituent of the substrate is oxidized anaerobically by whole-cell suspensions of PC-07 through a series of dehydrogenation and hydration reactions to yield p-hydroxybenzoate (pOHB) in stoichiometric proportions. The partially oxidized intermediates in the pathway p-hydroxybenzyl alcohol and p-hydroxybenzaldehyde can also serve as substrates for pOHB formation. Nitrate is required as the external electron acceptor and is reduced to molecular N2. Reduction of the nitrate is stoichiometric, with pCr serving as the electron donor. In addition, the molar relationship between the electron acceptor (NO3-) reduced to the electron donor oxidized decreased to approximately 2:3 and then to 1:3 when p-hydroxybenzyl alcohol or p-hydroxybenzaldehyde, respectively, served as substrates. The decreased ratios were to be expected when the partially oxidized intermediates served as substrates, because they provided correspondingly less reducing power for pOHB formation. The anaerobic oxidation of pCr by PC-07 demonstrates a mechanism whereby aromatic compounds can be transformed in anoxic environments.